Block signaling system for railroads



(No Model.) 3 Sheets-Sheet 1.

M. S. OONLY.

BLDG-K SIGNALING SYSTEM FOR RAILROADS No. 431,917. Patented June 24,1890.

II II (No Model.) 3 Sheets-Sheet 2. M. s. OONLY.

BLOCK SIGNALING,SYSTEM FOR RAILROADS. N0..431,017. Patented June 24, 1890.

(No Model.) 3 Sheets-Sheet 3.

M. S. GONLY. BLOCK SIGNALING SYSTEM FOR RAILROADS.

N0. 431,01'7.- v Patented June 24, 1890.

is re UNITED STATES PATENT OFFIoEl.

MAHLON S. CONLY, OF HYDE PARK, ILLINOIS.

BLOCK SIGNALING SYSTEM FOR RAILROADS.

SPECIFICATION forming part of Letters Patent No. 431,017, dated June 24, 1890.

Application filed February 15, 1889. Serial No. 300,025. (No model.)

To all whom it may concern:

Be it known that I, MAHLoN S. OONLY, a citizen of the United States, residing in the Village of Hyde Park, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Block Sig-' naling Systems for Railroads, of which the following is a specification.

This invention relates to improvements in that class of railroadsignals commonly known as block-signals,because of the road being divided thereby into a series of blocks or sections, at each end of which a signal is located, so that when a train passes into a block it will throw a target or signal at the end of the block behind the train, or at each end of the block behind and in front of the train, and when passing beyond the block will withdraw the signals thrown therein and set the signals in the next block in which it enters, and so on to the end of the line.

The prime object of this invention is to opcrate simultaneously one or more pairs of signals controlled by electro-magnets coupled in series and operating upon a closed circuit.

Another object is to operate successively one or more pairs of a series of signals controlled by a corresponding series of electromagnets working upon a closed circuit.

Another object is to have such signals when operated so adapted and arranged that one of the signals of each pair will be set and the other simultaneously withdrawn from view.

A further object is to have the closed circuit so arranged that the bridging or shortcircuiting of any electro-magnet will cause the signal thereof to be set or thrown into view, and which magnet, simultaneously with the cutting out or bridging of the next succeoding magnet, will be again restored to the circuit.

A still further object is to combine with the closed primary circuit bridging or short circuits,includingtrack-instrumentsdesigned to temporarily close the short circuit and cut out a primary electro-magnet on the passage of a train over said instrument, and also relay or secondary magnets for each of the primary magnets adapted and arranged to maintain the short or bridging circuit when established until the next primary magnet is cut out or bridged, and,.finally, to combine with such a system a track-instrument of novel and peculiar construction, especially adapted for use in connection with such a system, whether used upon a single or double track railway.

The system of block-signals, hereinafter described, is equally adapted for use upon either a single-track or double-track railway, the essential features of the system remaining the same in both cases, with only such changes in the Wiring or electrical circuit as will adapt the devices for use in connection with one or the other systemsthat is to say, that while on a double-track railway, in which all the trains run in the same direction on each track, it is customary and only necessary to throw a signal behind the train, on a single-track railway it is customary and necessary to throw a signal both in front and behind the train, and obviously the circuits of two such systems must differ, although the essential features of the signaling system remain the same in both cases.

In the accompanying drawings 1 have shown in Figure 1 a diagram of a portion of a double-track railway with my block signaling system applied thereto, and in Fig. 2 is shown a similar diagram of. a single-track railway. Fig. 3 represents an enlarged vertical section of a track-instrument especially adapted for use in connection with my signaling system; Fig. 4:, a horizontal sectional view thereof; Fig. 5, a transverse vertical section thereof Fig. 6, a detail sectional view 011 the line 6 6 of Fig. 3, looking in the direction indicated by the arrows; and Fig. 7, adetail section on the line 7 7 of Fig. 3, looking in the direction indicated by the arrows.

Similar letters of reference indicate the same parts in the several figures of the drawings.

Referring first to the double-track system, illustrated in Fig. 1, A A indicate two tracks, respectively; B, B, and B the track-instruments, (shown arranged along one track only, because the operation on both tracks is identical, except that it is reversed as to direction of operation;) 0, O, and C the primary magnets or induction-coils, one for each traclc instrument; D, D, and D secondary or relay magnets corresponding in number and location with the primary magnets; E, E, and

disclose a red and white or other colored lights;

or the devices operated by the armature-lever may be of any suitable character that will convey to the engineer the proper signal, those herein shown being merely illustrated for clearness of description, as the particular construction of the signal proper forms no part of this invention, which may be employed in connection with any of the numerous devices now in use for this purpose.

Again referring to Fig. 1, H, H, and 1-1 indicate the vibrating armature of the secondary or relay magnets, constituting shunttongues for diverting the current of the main line, as hereinafter described; I, I, and I one of the contact-points, and K, K, and K the other contact-points, with which these shunt-tongues are designed to alternately en-.

gage; L, L, and L contact-springs adapted and arranged to be operated by the projecting ends M, M, and M of the armature-levers; N, N, and N and O, O, and O opposing pairs of contact-points,-with which the contact-springs are designed to alternately make contact. Thus it will be seen that for a double-track railway my system preferably consists of a series of target-signals each with its accompanyingelectro -magnet, track-instrument, and other operating devices disposed along each track, those along one track to be operated only by the trains which pass always in the same direction over that track, while the others are operated by the trains passing on the other track, so as to keep a signal visible behind the trains at all times, each track-signal falling into View or appearing as the train passes over the track-instrument connected therewith, so as to become visible, and the one last past rising or disappear-ing simultaneously therewith.

The electro-magnets of all the track-signals in each division, comprising as many blocks as can be worked by any desired strength of battery, are connected in series in the line and the line either grounded at the ends or connected with the terminals of the other line of targets along the other track, which latter is the preferred arrangement, for by it is established a complete metallic circuit comprising both lines, one serving as areturn for the other. By this arrangement one-half of the battery may beplaced at each end of the divisionand thus reduce the batteryower required and at the same time promote the effectiveness of its operation; but obviously,

iiithgither the metallic circuit or the grounded circuits, batteries may be inserted at any point on the line between targets, thereby enabling the operation of a division of unlimited length.

The secondary or relay magnets to be employed in connection with my system are what are commonly known as polarized relays that is, an instrument composed of an eleotro-magnet wound with fine insulated copper wire, a permanent magnet, and a softiron vibrating armature,constituting atongue, the latter so arranged and disposed that it is polarized by induction from one pole of the permanent magnet, and being pivoted between the poles of the electro-magnet of the relay is subject to vibration on the passage of an alternating current, or of electrical impulses of different directions through the cores of the electro-magnets.

The primary magnets c, c, and c are differently wound,one coil of coarse wire of low resistance and the other coil of fine wire of high resistance, the whole constituting in effect an induction-coil, and for convenience of description I will hereinafter designate these coils as primary and secondary, respectively. All of the primary coils are connected in series in the line-circuitthat is to say, the primary coil of each primary magnet is connected with that of the adjacent magnets so as to constitute one general primary circuit, including all of the primary magnets or induction-coils, which circuit is at all times closed, either through said magnets or through bridging or short circuits around them, for, as hereinafter described, the purpose 'of this invention is to successively bridge each one of the primary magnets temporarily by the action of a passing train, and thus operate the signals controlled thereby. All of the secondary coils of the primary magnets are connected with the relay or secondary magnets, so as to constitute the secondary circuits by means of which the primary magnets are temporarily bridged or cut out of the primary circuit; but this secondary circuit with the arrangement shown is never closed, excepting as between two adjacent relays between which the train is traveling, being broken at all the rest of the relays, and in effect only a series of short secondary circuits adapted to be successively closed and opened by the shunting of the primary circuit, for although one general secondary circuit, similar to that hereinafterdescribed in connection with a single-track railway, may be employed, this ITO mally open, but will be closed by the action of a passing train. This action, however, is almost instantaneous, and the closingotthe circuit at that point and consequent bridging of the primary magnet is only temporary, and unless otherwise controlled the circuit through the primary magnet would be immediately reestablished and the signals again withdrawn from view; but it is the purpose of this system to have the signal remain in sight continuously from the moment the train passes over the track-instrument until it passes over the track-instrument next ahead, which may be located a mile or more away, and between which two instruments the train may stop for an indefinite time at a station, or for any other cause. To accomplish this and effect the continuous bridging of the primary magnets, my relays and secondary circuits are employed, the action of which will now be described.

1 Referring to Fig. 1, in which the track-signals G and G are shown in their normal position out of sight, the target G thrown into sight, and the train between the instruments B and 13 after having passed over the former and actuated the signal connected therewith, moving in the direction indicated by the ar row, we will first trace out the primary circuit and its connections. The main line-wire 1, extending between each of the primary magnets, connects with the terminals of the primary coil of each magnet, establishing a closed circuit through all of the primary magnets which are thus connected in series in the line-circuit. From the line-Wire on one side of each primary magnet extend branch Wires 2, terminating at one of the contact-springs or plates 3 of the track-instruments, While from the opposing contactplate 4 of said instruments extend branch wires 5, connecting with the contact-points I, I, and I respectively, each of which contact-points is in turn connected by wire 6 with the line-wire on the opposite side of the primary magnets, the said wires 2, 5, and '6 constituting short or shunt circuits for cutting out the primary magnets whenever a train passes over the track-instrument, so as to complete the circuit at that point, the resistance through these branches being so small, as compared to the resistance of the primary coil in the primary magnet, as to shunt practically all of the primary current through the short circuits. Each of the wires 2 is also connected by the wires 7 with the vibrating tongues H, H, and H of the secondary magnets, which tongues are so arranged that as long as the primary magnets C, C, and O are in circuit the tongues will remain in contact with the points K, K, and K respectively; but immediately a primary magnet is cut out by the closing of the short circuit through a track-instrument and the current is shunted therefrom the impulse imparted thereby to the secondary magnet by induction will cause the tongue to swing over against the contact-point I, I, or 1 as the case.

may be, and remain in that position until a reverse impulse is imparted thereto by the re-establishment of the circuit through the primary magnet, which will by induction send a current through the secondary or re lay magnets in the opposite direction and cause the tongue to reverse its position, or swing back again to its normal position, and thus break the short primary circuit through it and the contact-point.

The secondary circuits extend in each direction from each relay-magnet, so that it may be completedand operated at either side thereof with the adjacent magnet on either side, according to the contact-point with which the contact-springs'L, L, and L engage. I will therefore first enumerate the wires employed in completing the two circuits, some of which are in both circuits. Be ginning with the line-wire 1, which constitutes one side of each of the secondary circuits, we proceed to the wire 2, and from thence by the wire 8 to the relay-coils D, D, and D the opposite terminals of which are connected by wires 9 with the contact-springs L, L, and L Traveling to the left from either magnet, the contact-points N, N, and N are connected by wires 10 with the secondary coils of the primary magnets C, O, and C the opposite terminals of which are conneeted by wires 11 with the contact-points O, O, and 0 it being understood that the said wires 10 and 11, never being included in a single closed circuit, are employed successively, according to the primary magnet which iscut out. Now with this understanding of the arrangement of the circuits we will assume that the train indicated by the truck P, upon the track A, is now between the track-instruments B and B travelingin the direction indicated by the arrow. At this time the direction of the primary and secondary circuits may be traced by the arrows upon the drawings, the heavy arrows indicating the primary circuit and the lighter arrows the secondary circuit, and it will be observed that at this time the primary magnets C and are in circuit, and the target-signals G and G actuated thereby elevated and supposed to be out of sight, while the primary magnet C is out out of the circuit, being bridged by the wires 2 and 7, tongue H, and wire 6, and the target G operated thereby supposed to have fallen into view. The secondary circuit, beginning at the spring L, comes out over the wire 10, through the secondary coil of the primary magnet 0 out through wire 11, to contact'point O to contact-spring L thence by wire 9 to relay-magnet D after leaving which it proceeds over the wire 8 and returns by way of the primary wires 2, 1, and 6, tongue H, wires 7, 2, and 8, relay-magn et D, and wire 9 back to the tongue L. It will also be observed that while the spring contact-plate L engages the contact-point N, because controlled by the armature-lever M, the contact-plate L is forcibly magnets O and O held in engagementvwith the contact-point O by the armature-lever M and also that while the armature-tongue H engages the contact-point I the armature-lever H engages the contact-point K The circuits and parts and elements thereof will remain in the position just described until the train passes over the track-instrument B closing the primary circuit thereat, whereupon the primary circuit will be shunted from the primary magnet 0 through the wire 2, trackinstrument B and wires 5 and 6, to the linewire 1 at the opposite side of the primary magnet, thus bridging or cutting out the said magnet. Simultaneously with the cutting out ofthis magnet, and as a result thereof, an impulse will be sent through the relaymagnet D causing the armature-tongue H thereof to swing over into contact with the point 1 and thus establish a short circuit through the wire 7, said tongue, and the wire 6, the track-instrument, after the passing of the train, reopening and breaking the circuit at that point, but of course without affecting the short circuit, which has been established as last described. Almost simultaneously with this action the same impulse causes the tongue H, which is also in this secondary circuit, to swing over against the contactpoint K, thus breaking the short or bridging primary circuit at this point and restoring the primary magnet C to this primary circuit, whereupon the armature F will operate to throw up the signal G out of View and move the contact-spring L off the contact-point N to the contact-point 0, thus breaking the secondary circuit between the Immediately following this action, now that the primary magnet O is out out, the gravity of the target-signal G2 will cause the latter to fall, lifting the end M thereof, and permitting the spring contactplate L to move over into engagement with the contact-point N and thus complete the secondary circuit through the magnet neXt to the left. Thus it will be seen that simultaneously with the falling of the target G2 into sight the'target-signal G is withdrawn from sight and its magnet restored to the circuit, and the parts will remain in this position until the train reaches the next instrument ahead, when the operation just described will be repeated. Now as to the single-track system represented in Fig. 2 of the drawings, and by which it is designed to throw a signal simultaneously behind and in front of the train, the elements composing the system are identical, or substantially so, withthose of the double-track system, there being the same primary magnets, secondary or relay magnets, vibrating armature-tongues, and track-instruments, all of which operate in substantially the same manner as in the double-track system, the secondary circuit, which is the essential feature of both systems, operating first to maintain and then break the short circuits for bridging the primary magnets. between the two systems shown in the drawings, although not necessary in actual prac-n it being understood that no matter in which direction the train is going, the signal at that point on one side of the track and at the opposite side of the track at a point to the rear will be withdrawn, and simultaneously a signal on the opposite side of the track at that point and on the same side of the track a suitable distance ahead will be thrown into view, thus making two sets of signals working simultaneously throughout the length of the system, one at each end of the block, instead of only'one set at the rear end of the block, as in the double-track system. Thus taking the signals in pairs at each end of the blocks on opposite sides of the tracks we will designate a as one signal, whose mate is not shown; b and b, the first pair in the blocks shown in the drawings, in the direction in which the train is moving; 0 and c, the next pairs, and d one of the succeeding pairs, whose mate is not shown. Then let e,f, and 9 indicate the track-instruments operating while the train is moving in the direction indicated in the drawings, and 72, 7;, and j the instruments which operate the signals when the train is moving in the opposite direction. The primary magnets in this, as in the first system described, are connected in series operating upon a closed primary circuit, which, when all of the targets are in their normal position, may be traced as follows over the heavy primary wires 12: first, to the magnet at the signal I), then to a, to c, to b, to d, to c, and so on throughout the system, bring ing each of the primary magnets at each track-instrument successively in the line. In the drawings, however, the train is supposed to be at the point indicated by the wheel K, between the track-instruments c and f, moving in the direction indicated by the arrow, at which time all of the signals excepting b and b are concealed, and these said signals thrown down into view; and at this time the primary circuit may be traced by following the heavy arrows of the drawings, which show the primary magnet of both signals 1) and I) circuit. The secondary circuit may also be traced by following the lighter arrows,which show the line-wire 12 as constituting a part of the secondary circuit, which is'the case in both of these systems. When the train crosses the track-instrument f, thereby'bridging on There is this difference, however,

IIO

short-circuiting theprimary magnet of the signal c and restoring the primary magnetb to the circuit, two impulses will be sent out over the secondary circuits, one to the rear from the relay-magnet of the signal I) to that of the signal Z) and another to the front from the relay-magnet of the signal 0 to that of the signal 0', the first of which will serve to break the short circuit bridging the primary magnet of the target I), restoring it to the circuit and simultaneously establishing a short circuit bridging the primary magnet of the signal 0. This is accomplished as follows: The momentary closing of the circuit by the contact between the upper and lower plates 13 and 14 of the track-instrument establishes a short circuit through the wires 15, 16, and 17, bridgin g the primary magnet of the signal 0, which sends out by induction an impulse through the relay or secondary magnet thereof, causing its armature-tongue 18 to swing overinto contact with the opposite contact-point 19, and thus establish a permanent short circuit through wire 20, the middle tongue 21 of the track-instrument i, and wire 22 back onto the main line. The same secondary impulse proceeding by wire 23 to the relay-magnet of the signal 0 causes the tongues 24 thereof to swing over against the contact-point 25, establishing a short circuit bridging the primary magnet of said signal through the me dium of wire 26, leading from the contactpoint 25 to the middle plate 27 of the trackinstrument g, and thence through the bottom plate 14 and wire 28 to the main-line wire, through which wires the primary current will pass around to the tongue 24, thence by the wire 29 to the primary line-wire 12 at the opposite side of the primary magnet. The bridging or cutting out of the primary magnets of the signals 0 and 0 will cause them to simultaneously fall into view, throwing a signalbehind the train as it passes over the instrument f, and also one in front thereof, both of which will remain in view until the train crosses the next traclcinstrument J. As before described, the operation of the track instrument f by the passing train causes the primary circuit to temporarily pass through the wires 15 16, spring contact-plates 13 and 14 of said instrument, and wire 17 onto the'line-wire 12 of the primary circuit, and that as soon as the train has passed and the circuit is again broken at the track-instrument it is permanently established through the wire 15, armature-tongue 18, wire 20, contact-plates 14 21, track-instrument t, and wire 22 onto the main-line wire, thus restoring the primary magnet of the signal I) to the circuit, for simultaneously with the closing of the primary circuit through the track-instru ment f, the short circuit through that instrument, as indicated by the heavy arrows, is broken by the separation of the middle and bottom contact-plates thereof, and the primary current necessarily passes through the primary magnet of the signal 11, which produces an instantaneous impulse by induction through the relay-magnet thereof, causing the tongue 30 to swing over against the contact-point 31, thus permanently breaking the short circuit; and simultaneously with this action the impulse extends along the Wire 32 back to the secondary or relay magnet of the signal 19, causing the tongue 33 thereof to swing over against the contact-point 34, and thus break the short circuit bridging the primary magnet of the signal 1). Immediately upon the restoration of the primary magnets of the signals 1) and b to the primary circuit the said signals will be actuated by the magnets and withdrawn from sight, thus showing that the track is clear in the block at each end of which they are located. All of, the operations just described of the magnets actuating the signals 1) and Z), c and 0', take place almost simultaneously, thus serving to withdraw the signals from the block last passed through and throwing the signals at each end of the block on which the train is about to enter, and this action will be repeated successively throughout the entire system. Obviously this system could be employed on a single as well as a double track, it being only necessary to equip each track with the devices herein described; and so, also, might the system first described and shown in Fig. 1 be employed on a single-track system but practice has demonstrated that it 1s unnecessary to have but a single signal, and that behind the trains, on a double-track railway, because all of the trains move 1n the same direction on each track, while on a S111- gle-track railway, on which the trains move in both directions, a signal should be thrown up both behind and in front of the train, and for that reason the systems are herein described and illustrated separately, although the elements employed in both systems are identical, the only difference being in the number and location of the instruments and the wiring between them, which latter, however, if desired, may be the same. The trackinstruments to be employed in connection with these systems may be of any suitable form that will accomplish the desired result, a number of which are in use at the present time; but I prefer to employ the instrument of peculiar and novel construction illustrated in Figs. 3, 4, 5, 6, and 7 of the drawings, which instrument is especially adapted for use in connection with this system, combining some features which are not common to any other other, while the latter is normally out of contactwith both of said springs, but is adapted to make contact'with the spring Z, the act of making which contact breaks contact between springs Z and m, such an arrangement being necessary in the use of a double circuit, such as is shown in Fig. 2 of the drawings. The adjustable spring a is operated by means of a piston-rod o, to which it is secured by IO insulating-washers 0, said rod working through and is guided at its upper end by a bracket 13, while-its lower end projects into a closed air-cylinder p, and has rigidly secured thereto a piston 19 working in said cylinder in the manner hereinafter described. All of these parts are inclosed in a casing q, of any desirable form or construction, so as to pro- I tcct them from the elements, the air-cylinder 19 being suspended from links (1, attached 20 at their upper ends to the inner free end of a bifurcated lever 0', pivoted at r in the casing q, the outer end r of which lever is also bifurcated to receive the flange S of the rail S between the ends thereof, so that any movement of the rail, either up or down, will produce a corresponding movement of the lever upon its pivot. Thus whenever a train passes over an instrument the weight thereof will cause the rail to be depressed momenta- 3o rily, and thus elevate the airchamber p, the

air in which will cause a corresponding elevation of the piston and piston-rod, and hence produce contact between the springs n and Z, and with the result hereinbefore described.

5 As soon as the train passes the track will spring back to its normal position and reverse the position of these parts. The employment of a yielding connection between the lever and spring n, provided by the 40 air-chamber and piston, enables the auto- 'matic adjustment of the instrument to the varying conditions of the elements which produce corresponding variation in the rela tive position of the track and instrument that is to say, the gradual swelling or sinking of the ground in cold or damp weather produces a corresponding rise or fall of the track-instrument; but such action is so gradual that the air in. the air chamber has suffi- 5o cient time to pass from one side of the piston to the other, whether its position be higher or lower in the said chamber, and thus establish an equilibrium on each side thereof, without effect upon the contact-plate, except when directly actuated by the weight of a passingv train.

It will be understood that in both the specification and claims the term relay or secondary magnets is employed to designate a magnet operating upon a secondary or induced current from the primary magnets, as distinguished from magnets sometimes called secondary because of secondary importance and'operation, but which in reality are small primary magnets operated by the primary current when shunted through them,

nets, substantially as described.

2. In a block signaling system for railroads, the combination, with a series of signalsand a corresponding series of electromagnets for operating the same, said magnets being coupled in series and Working on a closed electric circuit, of a series of relay or secondary magnets operating by induction from said signal-magnets for temporarily and successively bridging or short-circuiting each signal-magnet, substantially as described.

3. In a block signaling system for railroads, the combination, with a series of signals and a corresponding series of electromagnets for operating the same, said magnets being coupled in series and working on a closed electric circuit, of a series of relay or secondary magnets operating by induction from said signal-magnets for temporarily and successively bridging or short-circuiti n g each signal-magnet and simultaneously restoring to the circuit the adjacent signal-magnet previously cut out, substantially as described.

4. In a block signaling system for railroads, the combination with a series of signals and a corresponding series of electromagnets, said magnets being coupled in series and working on a closed electric circuit,

of a series of relay or secondary magnets operating by induction from said signal-men,- nets, a series of track-instruments operated by the train to close a short circuit, and there'- by temporarily bridge the primary magnet corresponding therewith, and devices oper ated by said relay-magnet for maintaining said short circuit, substantially as described.

5. In a block signaling system for railroads,

the combination, with a series of signals and a corresponding series of electro-magnets op erating the same, said magnets being coupled in series and working on a closed circuit,

of a series of relay or secondary magnets operating upon a secondary circuit by induction from said primary electro-magnets, vibrating armature-tongues for said relaymagnets, and a series of track-instruments operated by the train to close a short circuit, and thereby bridge the primary magnet, whereby when the primary magnet is bridged the armature-tongue of the relay-magnet will be actuated so as to maintain such short circuit, substantially as described.

6. In ablock signaling system for railroads, the combination, with a series of signals and a corresponding series of electro-magnets op erating the same, said magnets being coupled in series and working on a closed electric circuit, of a series of secondary or relay magnets, also coupled in series and operating by induction from said primary electro-magnets, vibrating armature-tongues for each of said relay-magnets, and a series of track-instrtb ments operated by the train to temporarily close a short circuit, and thereby bridge the primary magnet corresponding therewith, whereby when the primary magnet is bridged the armature-tongue of the corresponding relay-magnet will be actuated, so as to maintain such short circuit, and simultaneously therewith the armature-tongue of the adjacent relay-magnet will be actuated to break the short circuitand restore its primary magnet to the closed electric circuit, substantially as described.

7. In a block signaling system for railways, the combination of a series of signals, a series of primary electro magnets operating the same and working upon a closed electric circuit, a corresponding series of relay or secondary magnets, each pair of which is in circuit, said magnets co-operating with the primary magnets, so as to operate by induction therefrom, mechanism for temporarily shortcircuiting each of said primary magnets, and mechanism operated by the relay-magnets alternately maintaining and breaking said short circuits, substantially as described.

8. In a block signaling system for railways, the combination of a series of signals, a series of electro-magnets for actuating the same, operating upon a closed electric circuit, aseries of secondary magnets operating by in duction from the primary magnets, each pair of said secondary magnets being in circuit, vibrating armature-tongues for said secondary magnets, a series of track-instruments for temporarily short-circuiting each of said primary magnets, said armatures co-operatin g with the short circuits so as to alternately maintain and break the same, substantially as described.

9. In ablock signaling system forrailroads, the combination, with a series of signals and a corresponding series of electro-magnets operating the same, said magnets being coupled in series and working in a closed electric circuit, of a series of relay or secondary magnets coupled in series, vibrating armaturetongues therefor, and a series of track-instruments normally closing a short circuit and co-operatin g with the same so as to break such short circuit, and simultaneously but temporarily close the main primary circuit therethrough, substantially as described.

10. In a block signaling system for railroads, the combination, with a series of signals and a corresponding series of electromagnets operating the same, said magnets being coupled in series and Working on a closed electric circuit, of a series of relay or secondary magnets coupled in series and operating by induction from said signal-magnets, and a series of track-instruments for temporarily short-circniting each of said primary magnets, each of said instruments comprising circuit making and breaking devices, a lever for operating the same connected with and actuated by the rail, and an adjustablyyielding connection between said lever and devices, substantially as described.

11. In a block signaling system for railroads, the combination, with a series of signals and a corresponding series of electromagnets operating the same, said magnets beingcoupled in series and working 011 a closed electric circuit, of a series of relay or secondary magnets coupled in series, vibrating armature-tongues therefor, and a series of track-instruments for temporarily shortcircuiting each of said primary magnets, said track-instrument comprising a vertically-reciprocating piston and rod, a vertically-reciprocating closed cylinder in which said piston works, opposing contact-springs, one of which is free and the other attached to and operated by the piston-rod, a contact-plate normally in contact with the free contactspring, a lever bifurcated at one end for re ception of the rail-flange, and a link-connection between said lever and a closed cylinder, substantially as described.

MAnLoN s. CON-LY.

Witnesses:

W. R. OMOI-IUNDRO, A. M. BENNETT. 

